Production of lime



(No Model.)

I Jv..' F. BARROW.

PRODUCTION 0? LIME.

Patented Oct. 3, 1893.

WITNE5SEE- K di jw UNITED STATES JACOB F. BARROW, OF

PATENT OFFICE.-

PRODUCTION OF LIME.

SPECIFICATION forming part of Letters Patent No. 506,029, dated October 3, 1893.

Application filed January 14, 1893. Serial No. 458,311. (No model.)

To all whom it may concern.-

Be it known that I, JAooB F. BARROW, of Parole, in the county of Anne Arundel and State of Maryland, have invented certain Improvements in the Burning of Limestone for the Production of Lime, of which the following is a specification.

The object of this invention, in common with others of its class, is to render possible the use of coal alone, or gas or hydrocarbon as a fuel in the burning of lime stone, and it consists, first, in the method of rapidly carrying 01f the carbonic acid gas eliminated in the burning of the lime stone, and effecting or facilitating the entrance of air to the burning coal, gas or oil, whereby the combustion of the same is rendered as nearly perfect as possible, and the heated products of combustion diffused throughout the lime stone and carried off, so as not to interfere with the combination with the fuel of the fresh air as it enters.

The invention consists, secondly, in the means used to accomplish the above described results, as will hereinafter fully appear.

In the further description of the said invention which follows, reference is made to the accompanying drawings forming a part hereof and in which Figure 1 is an exterior perspective View of a lime kiln provided with the present invention. Figs. 2 and 3 are respectively, an exterior front, and a side section of the improved lime kiln on an enlarged scale.

Referring to the drawings, A represents the lime kiln which in Fig. 1 is shown as built in a space formed in the side of a hill, so as to give convenient access to the charging and firing doors, and also to the aperture through which the burned lime is withdrawn.

The furnaces of the kiln are represented by B, and the bosh or portion of the kiln in which the lime stone is burned is denoted by O.

D D are the furnace doors, which are made so as to close practically air tight on the frame a.

E is the charging aperture through which the lime stone is introduced to the bosh, and it is provided with a door F which closes tightly on the frame I).

The portion of the kiln above the bosh and in which is situated the charging door E has an aperture 0 covered by a hinged door or Valve H, preferably arranged so that it may be opened by means of a cord or chain from the lower part of the kiln, as shown in Fig. 1.

J is an exhausting fan or blower situated at a convenient distance from the kiln and connected by a draft pipe L to the interior of the kiln above the bosh. This fan is driven in any appropriate manner, and when in motion and the furnace and charging doors and the valve H closed, air is drawn through the grate bars to the furnace. The air thus drawn into the furnace combines with the carbonof the coal or other fuel, and a nearly complete combustion of the same is effected. The heated products of combustion are drawn through the interstices between the lumps of lime stone and the stone burned, the said products being eventually discharged from the fan. In view of the draft pipe L being so much smaller than the bosh of the kiln, the heated products of combustion are not forced to take a rapid course through the center of the bosh, but are difiused throughout the entire body of lime stone and a much better result is produced than if a natural draft were used, or a forced draft by means of a blower efiected. Where a forced draft is effected by means of a blast introduced to the ash pit, the carbonic acid gas resulting from combustion is not carried ahead of the air but forms eddies and is mixed with the air, thus interfering with the combustion. But where the pressure in the kiln is reduced by drawing off the carbonic acid gas and other products of combustion the incoming air is not mixed with them and a more nearly perfect combustion of the oxygen of the air with the coal produced.

It is evident that a steam jet M placed in the lime kiln above the lime stone as shown cally the same effect as the exhaust fan.

When such jet is used the damper or valve H furnace without mixing to an appreciable exwill not be necessary. tent with the said products, substantially as I0 I claim as my inventionspecified. The method of burning lime stone for the JACOB F BARROW 5 production of lime herein described, which consists in exhausting the carbonic acid gas Witnesses: and other products of combustion from the WM. T. HOWARD, bosh of the kiln so that the air may enter the DANL. FISHER. 

